Classical Numismatics Discussion
  Welcome Guest. Please login or register. STORE WIDE SALE!!! 10% OFF EVERYTHING UNTIL 3 FEBRUARY Layaway and reserve are not available during the sale Shop NOW and save! Welcome Guest. Please login or register. STORE WIDE SALE!!! 10% OFF EVERYTHING UNTIL 3 FEBRUARY Please call us if you have questions 252-646-1958 Shop NOW and save!


FORVM`s Classical Numismatics Discussion Board  |  Numismatic and History Discussions  |  Coin Photography, Conservation and Storage  |  Topic: Medic!!!! Question from the ER 0 Members and 1 Guest are viewing this topic. « previous next »
Pages: [1] Go Down Print
Author Topic: Medic!!!! Question from the ER  (Read 2264 times)
Ghengis Jon
Caesar
****
Offline Offline

Posts: 660



« on: April 30, 2008, 04:00:20 pm »

This is a painful experience for me.  I received this coin earlier this week.  (Top photo is the seller's shot)  As I took it out of the flip it shipped in, a chunk of the patina broke off (aaarrrrggggghhhh!).  The coin is nearly 3mm thick with patina accounting for about half the thickness.  Under the patina was revealed to be a core of metal that has a white dusty appearance.  The second shot is how it currently looks and the last is a close up of the damage.

The rest of the coin is in good shape (o cracks or chips).  But the 'powdery' metal concerns me.  How should his coin be preserved (as opposed to conserved)?  Should I worry about moisture in the air and further coin decomposition?  Wax will not buff out imo and would be unsightly.  Should I seal the exposed area with polyeurathane or the like?  Should I just live with it and do nothing?

Opinions please from the esteemed membership.  Thanks, Jon
Logged

Don't buy uncleaneds from ebay's ancientcoinman - 70% slugs and NO returns!
Ghengis Jon
Caesar
****
Offline Offline

Posts: 660



« Reply #1 on: April 30, 2008, 04:01:29 pm »

Close up of the damage
Logged

Don't buy uncleaneds from ebay's ancientcoinman - 70% slugs and NO returns!
museumguy
Caesar
****
Online Online

Posts: 447


I know nothing except the fact of my ignorance.


« Reply #2 on: May 01, 2008, 06:02:12 am »

Jon,

Since you are in Michigan I would take advantage of the terrific conservation staff at the Detroit Institute of Arts.  I'm sure they would be more than happy to give you some free advice and they certainly know what they're talking about.  I've attached the link to their online contact form.  You can send it directly to their conservation department.  Good luck.

Steve

http://www.dia.org/museum_info/contact_us/index.asp
Logged

Robert_Brenchley
Procurator Caesaris
Caesar
****
Offline Offline

Posts: 7328

Honi soit qui mal y pense.


WWW
« Reply #3 on: May 04, 2008, 10:17:02 am »

I've come across this when I dropped a Carausius, in its flip, onto a carpetted floor, and it chipped. I think it's the same thing in both cases; the metal has been completely corroded away leaving nothing but carbonates, which are excessively fragile.
Logged

Robert Brenchley

My gallery: http://www.forumancientcoins.com/gallery/index.php?cat=10405
Fiat justitia ruat caelum
Ghengis Jon
Caesar
****
Offline Offline

Posts: 660



« Reply #4 on: May 09, 2008, 06:52:42 am »

Did you 'treat' the chipped coin in any way after that?
Logged

Don't buy uncleaneds from ebay's ancientcoinman - 70% slugs and NO returns!
Ghengis Jon
Caesar
****
Offline Offline

Posts: 660



« Reply #5 on: May 16, 2008, 12:13:31 pm »

I received a response from one of the conservators at the DIA...

The metal in the coin has largely become mineralized probably as a result of being buried. This would make the body brittle and powdery. Although I don't think you need to do anything except keep the coin dry, you could brush on a bit of 3% Paraloid B-72 acrylic resin in acetone or ethanol just at the exposed area to consolidate the edge. B-72 is available on line, and you can get solvents at your local hardware store.
Logged

Don't buy uncleaneds from ebay's ancientcoinman - 70% slugs and NO returns!
Robert_Brenchley
Procurator Caesaris
Caesar
****
Offline Offline

Posts: 7328

Honi soit qui mal y pense.


WWW
« Reply #6 on: May 31, 2008, 03:00:39 pm »

Did you 'treat' the chipped coin in any way after that?

Sorry, I missed this one. No, I didn't feel I could do anything with it. It's a common and inexpensive coin, and illustares corrosion very nicely!
Logged

Robert Brenchley

My gallery: http://www.forumancientcoins.com/gallery/index.php?cat=10405
Fiat justitia ruat caelum
Pages: [1] Go Up Print 
FORVM`s Classical Numismatics Discussion Board  |  Numismatic and History Discussions  |  Coin Photography, Conservation and Storage  |  Topic: Medic!!!! Question from the ER « previous next »
Jump to:  

Recent Price Reductions in Forum's Shop


Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!
Page created in 0.553 seconds with 34 queries.
zoom.asp